Apple on Wednesday released a widespread developer beta version of its Mac OS X 10.6.4, the fourth maintenance and security update for its Snow Leopard operating system. Until now, the future OS had been under development internally for several weeks.

According to AppleInsider, the beta, labeled Mac OS X 10.6.4 build 10F37, made its way to Apple Developer Connection (ADC) members just one day after a more elite set of testers belonging to Apple’s Apple Seed program were able to test the beta.

According to sources familiar with Wednesday distribution, Apple has asked developers to test four key areas of the system, including graphics drivers, Windows file sharing, USB devices and Voice Over.

Although the build released to ADC members on Wednesday is identical to the one issued to Apple Seed members on Tuesday, an emphasis on evaluating Time Machine backups noted in the Apple Seed distribution was not extended to the ADC version.

It’s unclear what specific issues Mac OS X 10.6.4 will target upon its release, as Apple reportedly stopped short of including a list of enhancements with either of the aforementioned distributions.

That said, the updated build could arrive sooner than later given that the Mac maker went through 36 builds internally before tapping its developer community to put its weight on the software.

Apple listed only one known issue in documentation accompanying Wednesday’s build: that iChat will require a password each time it’s launched.